// Copyright 2016 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CONTENT_RENDERER_PEPPER_PEPPER_AUDIO_CONTROLLER_H_
#define CONTENT_RENDERER_PEPPER_PEPPER_AUDIO_CONTROLLER_H_

#include <set>

#include "base/macros.h"

namespace content {

class PepperPluginInstanceImpl;
class PPB_Audio_Impl;

/**
 * This class controls all the active audio instances of a Pepper instance.
 * This class can only be a non-shareable member of PepperPluginInstanceImpl.
 */
class PepperAudioController {
public:
    explicit PepperAudioController(PepperPluginInstanceImpl* instance);
    virtual ~PepperAudioController();

    // Adds an audio instance to the controller.
    void AddInstance(PPB_Audio_Impl* audio);

    // Removes an audio instance from the controller.
    void RemoveInstance(PPB_Audio_Impl* audio);

    // Sets the volume of all audio instances.
    void SetVolume(double volume);

    // The pepper instance has been deleted. This method can only be called
    // once. The controller will be invalidated after this call, and then all
    // other methods will be no-op.
    void OnPepperInstanceDeleted();

private:
    // Notifies the RenderFrame that the playback has stopped.  This method should
    // only be called when |ppb_audios_| turns from non-empty to empty.
    void NotifyPlaybackStopsOnEmpty();

    // All active audio instances.
    std::set<PPB_Audio_Impl*> ppb_audios_;

    // The Pepper instance which this controller is for. Will be null after
    // OnPepperInstanceDeleted() is called.
    PepperPluginInstanceImpl* instance_;

    DISALLOW_COPY_AND_ASSIGN(PepperAudioController);
};

} // namespace content

#endif // CONTENT_RENDERER_PEPPER_PEPPER_AUDIO_CONTROLLER_H_
